In a welding method the substrate of a component is melted so that cracks in the substrate are sealed, optionally with the addition of an auxiliary welding material, particularly in the form of powder, which is also melted and allowed to solidify during the welding.
Particularly for directionally solidified components, which have a longitudinally directed grain structure or consist of a single crystal, such welding methods are also used in order to set up a directionally solidified structure in the welded region.
The problem with the welding method, however, is that the process does not already take place stably from the start, so that the sites which are welded first often have inferior properties compared with the other welded regions and they often have to be melted once more.